Yet another scientific(?) study of "stopping power."

[tpd223]

I always find it refreshing when real world observations agree with lab testing.

In the past that was actually an issue. Anyone else recall the RII crap from like the 1970s, IIRC? That was where rounds such as the 110gr +P+ .38 special came from.

[481]

Thanks for confirming what I thought he was trying to say. No pun was intended by my mention of Jello.

And I've learned a new phrase, too.

I'll lay it on my wife and enjoy the look of annoyed confusion on her face. She already thinks I am nuts and this'll push her over the edge.

[Reagans Rascals]

Stopping power means just that... the amount of force it hits with. Internal ballistics and wound cavities and this and that have no place when talking in terms of stopping power. A .44 magnum is going to have much more stopping power than a 9mm, plain and simple. Law of momentum... One round might be more lethal in terms of yawing effects once inside but stopping power means having the most force to flat out put a target down right when it is hit, not when it succumbs to fatal injuries later. Therefore, the harder hit of the heavier round wins.

A semi-truck impact will trump a car impact any day of the week.....

[tpd223]

Seriously, you did not just post that.

[481]

Anyone else recall the RII crap from like the 1970s, IIRC? That was where rounds such as the 110gr +P+ .38 special came from.

Yep. Whenever I see pictures of the "computer man", it reminds of an unsophisticated attempt at finite element analysis.

For the early attempt that it was, the Thompson-LaGarde tests produced pretty decent correlation for the relative performance of non-expanding projectile designs and is addressed by Duncan MacPherson on pages 270-275 of his book, "Bullet Penetration".

Who'da thunk it?

[481]

Seriously, you did not just post that.

It would appear that he did.

It is said that one should go to bed with little laughter.

I have mine now and I am out for the evening.

Thanks, Reagans Rascals.

[Reagans Rascals]

Seriously, you did not just post that.

enlighten me with your infinite wisdom

[billyjmc]

@tpd223, if only this site had a "like" button. :P

@Reagan, I'm no physicist, but here's my understanding of it…

More mass and or velocity simply does not make a round better able to knock over a target; it's entirely possible to cleanly punch a hole through a target without knocking it over – this is what you do when you shoot paper. Surely any bullet has sufficient kinetic energy to "knock down" a sheet of paper stapled to a cardboard stand, but if you can't transfer the energy completely, it does you no good. Any bullet that doesn't stop inside the target is "wasting" energy.

Nevermind the fact that the force propelling the bullet forward is the same amount of force driving the shooter back from recoil… if a gun doesn't "knockdown" a flatfooted shooter, the projectile cannot "knockdown" the shootee.

[Reagans Rascals]

@tpd223, if only this site had a "like" button. :P

@Reagan, I'm no physicist, but here's my understanding of it…

More mass and or velocity simply does not make a round better able to knock over a target; it's entirely possible to cleanly punch a hole through a target without knocking it over – this is what you do when you shoot paper. Surely any bullet has sufficient kinetic energy to "knock down" a sheet of paper stapled to a cardboard stand, but if you can't transfer the energy completely, it does you no good. Any bullet that doesn't stop inside the target is "wasting" energy.

Nevermind the fact that the force propelling the bullet forward is the same amount of force driving the shooter back from recoil… if a gun doesn't "knockdown" a flatfooted shooter, the projectile cannot "knockdown" the shootee.

we are not talking about shooting paper, which has no ability to absorb impact, it simply allows the round to pass right through. We are talking about targets with actual mass, such as a human torso. If I fire a larger grain round such as a .45 acp it will transmit more momentum into said target than a round of smaller mass. It is basic physics. Have a man in a SAPI plate, I shoot him in the chest with a .45, and then I shoot him in the plate with a 9mm. The potential energy absorbed by the plate is higher with the .45 than the 9mm. Basic physics once again.

If both rounds were hollow points, the larger round will win due to momentum.

As as for the comment on Newtons Second Law. There are devices within modern weapons that reduce the perceived effect. Especially present in semi-automatic weapons in which the rearward force is absorbed into springs and the reloading action of the weapon. It is still occurring but it not as noticeable as with a bolt action weapon.

[DocGKR]

"Stopping power means just that... the amount of force it hits with. Internal ballistics and wound cavities and this and that have no place when talking in terms of stopping power. A .44 magnum is going to have much more stopping power than a 9mm, plain and simple. Law of momentum... One round might be more lethal in terms of yawing effects once inside but stopping power means having the most force to flat out put a target down right when it is hit, not when it succumbs to fatal injuries later. Therefore, the harder hit of the heavier round wins."

This is completely erroneous. You might wish to review: https://www.m4carbine.net/showthread.php?t=34714